sched_setparam() - Unix, Linux System Call

NAME

SYNOPSIS

#include <sched.h>

int sched_setparam(pid_t pid, const struct sched_param *param);

int sched_getparam(pid_t pid, struct sched_param *param);

struct sched_param {
...
int sched_priority;
...
};

DESCRIPTION

sched_setparam() sets the scheduling parameters associated with the scheduling policy
for the process identified by pid. If pid is zero, then
the parameters of the current process are set. The interpretation of
the parameter param depends on the scheduling
policy of the process identified by
pid. See
sched_setscheduler(2)
for a description of the scheduling policies supported under Linux.

sched_getparam() retrieves the scheduling parameters for the
process identified by pid. If pid is zero, then the parameters
of the current process are retrieved.

sched_setparam() checks the validity of param for the scheduling policy of the
process. The parameter param->sched_priority must lie within the
range given by sched_get_priority_min(2) and
sched_get_priority_max(2).

For a discussion of the privileges and resource limits related to
scheduling priority and policy, see
sched_setscheduler(2).

POSIX systems on which
sched_setparam() and
sched_getparam() are available define
_POSIX_PRIORITY_SCHEDULING in <unistd.h>.

RETURN VALUE

On success,
sched_setparam() and
sched_getparam() return 0.
On error, -1 is returned, and
errno is set appropriately.

ERRORS

Tag

Description

EINVAL

The parameter param does not make sense for the current
scheduling policy.

EPERM

The calling process does not have appropriate privileges
(Linux: does not have the
CAP_SYS_NICE capability).